Answer:
Oxygen will dissolve more in H2O at 5 atm and 20 °C than at 5 atm 80 °C
Option B is correct.
Explanation:
Step 1: Data given
Pressure = 5 atm
Temperature = 20 °C or 80 °C
Step 2:
At low pressure, a gas has a low solubility. Decreased pressure allows more gas molecules to be present in the air, with very little being dissolved in solution. At high(er) pressure, a gas has a high solubility.
This means the higher the pressure the more the gas will dissolve. Since The pressure stays constant, it depends on the temperature.
The solubility of gases in liquids decreases with increasing temperature.
This means the gas will dissolve more with a lower temperature.
Oxygen will dissolve more in H2O at 5 atm and 20 °C than at 5 atm 80 °C
The atomic number defines the number of protons in an atom.
Answer:
True.
But it only changes in physical change.
How?
Explanation:
The chemical reaction produces a new substance with new and different physical and chemical properties. Matter is never destroyed or created in chemical reactions. The particles of one substance are rearranged to form a new substance.
In a physical change, a substance's physical properties may change.
A chemical change is a permanent change. A Physical change affects only physical properties i.e. shape, size, etc. ... Some examples of physical change are freezing of water, melting of wax, boiling of water, etc. A few examples of chemical change are digestion of food, burning of coal, rusting, etc.
Hope this helps!
Explanation:
Start with a balanced equation.
2H2 + O2 → 2H2O
Assuming that H2 is in excess, multiply the given moles H2O by the mole ratio between O2 and H2O in the balanced equation so that moles H2O cancel.
5 mol H2O × (1 mol O2/2 mol H2O) = 2.5 mol O2
Answer: 2.5 mol O2 are needed to make 5 mol H2O, assuming H2 is in excess.
69.9%
Explanation:
To find the mass percentage of iron in the compound in Fe₂O₃, we would go ahead to express the given molar mass of the iron to that of the compound.
Mass percentage = 
x 100
Molar mass of Fe = 55.85g/mol
Molar mass of O = 16g/mol
Molar mass of Fe₂O₃ = 2(55.85) + 3(16) = 159.7g/mol
Mass percentage = 
= 69.94% = 69.9%
learn more:
Mass percentage brainly.com/question/8170905
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